U.S. patent number 10,887,865 [Application Number 16/258,821] was granted by the patent office on 2021-01-05 for method for paging information in cellular system.
This patent grant is currently assigned to Electronics and Telecommunications Research Institute. The grantee listed for this patent is Electronics and Telecommunications Research Institute. Invention is credited to Seung Chan Bang, Soo Jung Jung, Jae Heung Kim, Jung Im Kim, Kyoung Seok Lee, Byung Han Ryu.
United States Patent |
10,887,865 |
Kim , et al. |
January 5, 2021 |
Method for paging information in cellular system
Abstract
Provided is a method for transmitting paging information in a
cellular system. An object of the method is transmitting paging
information which can improve applicability of a limited radio
resource by variably and flexibly setting up and mapping a
transport channel and a physical channel in order to transmit
information notifying start of downlink information from a base
station to a terminal in a cellular system for packet transmission.
The method includes the steps of: forming a paging channel (PCH) in
a transport channel corresponding to generation of paging
information; setting a paging indication channel (PICH) based on
the paging information and forming the paging indication channel in
a radio resource of a physical layer; and allocating the paging
channel to the radio resource of the physical layer.
Inventors: |
Kim; Jae Heung (Daejeon,
KR), Kim; Jung Im (Daejeon, KR), Lee;
Kyoung Seok (Daejeon, KR), Jung; Soo Jung
(Daejeon, KR), Bang; Seung Chan (Daejeon,
KR), Ryu; Byung Han (Daejeon, KR) |
Applicant: |
Name |
City |
State |
Country |
Type |
Electronics and Telecommunications Research Institute |
Daejeon |
N/A |
KR |
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Assignee: |
Electronics and Telecommunications
Research Institute (Daejeon-si, KR)
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Family
ID: |
1000005285935 |
Appl.
No.: |
16/258,821 |
Filed: |
January 28, 2019 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20190159171 A1 |
May 23, 2019 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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14844359 |
Sep 3, 2015 |
10231211 |
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14276511 |
Oct 6, 2015 |
9155066 |
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12298227 |
Jun 24, 2014 |
8761814 |
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PCT/KR2007/001997 |
Apr 24, 2007 |
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Foreign Application Priority Data
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Apr 26, 2006 [KR] |
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10-2006-0037522 |
Apr 20, 2007 [KR] |
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10-2007-0038849 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04W
68/02 (20130101); H04W 68/025 (20130101); H04L
5/0053 (20130101); H04W 72/042 (20130101) |
Current International
Class: |
H04W
68/02 (20090101); H04L 5/00 (20060101); H04W
72/04 (20090101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Other References
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.
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applicant .
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DoCoMo, Fujitsu, Mitsubishi Electric, NEC, Toshiba Corporation
("R2-060837"). cited by applicant .
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#53, by Motorola ("R2-060942"). cited by applicant .
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and RAN WG2 on LTE, Athens, Greece, Mar. 27-31, 2006 ("R2-060849").
cited by applicant .
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Athens, Greece, Mar. 27-31, 2006 ("R2-060865"). cited by applicant
.
R2-060913, User ID assignment during initial access, Mar. 27-31,
2006, Joint RAN WG1 and WG2 on LTE, by IPWireless ("R2-060913").
cited by applicant .
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RAN1/RAN2 meeting on LTE, by CATT("R2-060988"). cited by applicant
.
3GPP Technical Report 25.814 v1.2.2 ("TR 25.814 v1.2.2"). cited by
applicant .
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applicant .
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TSG-RAN WG2#56 Riga, Latvia, Nov. 6-10, 2006 ("R2-063275"). cited
by applicant .
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#48 by LTE rapporteur (NTT DoCoMo) ("R1-070753"). cited by
applicant .
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Antipolis, France, Jan. 9-13, 2006, by Panasonic ("R2-060007")
(submitted in place of R1-060007 cited in Appendix B). cited by
applicant .
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TSG-RAN WG1 LTE AdHoc, by Ericsson("R1-060093"). cited by applicant
.
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Sophia-Antipolis, France, Jan. 9-13, 2006 ("R2-060015"). cited by
applicant .
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#52, by Motorola ("R2-060945"). cited by applicant .
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22, 2019 for Case No. 2:18-cv-00526 Texas (E.D. Texas). cited by
applicant .
Intervenor Ericsson Inc.'s Preliminary Invalidity Contentions
submitted on Jul. 22, 2019 for Case No. 2:18-cv-00526 (E.D. Texas).
cited by applicant .
Exhibits B-1-B-10 for Defendant's Preliminary Invalidity
Contentions submitted on Jul. 22, 2019 for Case No. 2:18-cv-00526
(E.D. Texas). cited by applicant .
Appendix B for Defendant's Preliminary Invalidity Contentions
submitted on Jul. 22, 2019 for Case No. 2:18-cv-00526 (E.D. Texas).
cited by applicant .
Exhibits C-1-C-10 for Defendant's Preliminary Invalidity
Contentions submitted on Jul. 22, 2019 for Case No. 2:18-cv-00526
(E.D. Texas). cited by applicant .
Appendix C for Defendant's Preliminary Invalidity Contentions
submitted on Jul. 22, 2019 for Case No. 2:18-cv-00526 (E.D. Texas).
cited by applicant .
Exhibits AA-1-AA-10 for Defendant's Preliminary Invalidity
Contentions submitted on Jul. 22, 2019 for Case No. 2:18-cv-00526
(E.D. Texas). cited by applicant .
Appendix AA for Defendant's Preliminary Invalidity Contentions
submitted on Jul. 22, 2019 for Case No. 2:18-cv-00526 (E.D. Texas).
cited by applicant.
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Primary Examiner: Hong; Dung
Parent Case Text
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation application of U.S. patent
application Ser. No. 14/844,359, filed Sep. 3, 2015 (now pending),
which is a continuation application of U.S. patent application Ser.
No. 14/276,511, filed May 13, 2014 (now U.S. Pat. No. 9,155,066),
which is a continuation application of U.S. patent application Ser.
No. 12/298,227, filed Oct. 23, 2008 (now U.S. Pat. No. 8,761,814),
the disclosures of which are herein incorporated by reference in
their entirety. The U.S. patent application Ser. No. 12/298,227 is
a national entry of International Application No.
PCT/KR2007/001997, filed on Apr. 24, 2007, which claims priority to
Korean Application Nos. 10-2006-0037522 and 10-2007-0038849 filed
on Apr. 26, 2006 and Apr. 20, 2007, respectively, the entire
contents of which are incorporated herein by reference.
Claims
What is claimed is:
1. A wireless communication method, the method comprising:
receiving, at a user equipment, at least a part of a frame, wherein
(a) the frame consists of a plurality of transmission time
intervals (TTI) including a first TTI, (b) the first TTI comprises
a control channel and a shared channel, (c) first information is
received at the user equipment through the control channel of the
first TTI, and (d) at least a portion of the first information
identifies physical layer radio resources; determining, at the user
equipment, that an identifier is used in the first information; and
obtaining, at the user equipment, paging information transmitted
through the shared channel in the first TTI in response to
determining that the identifier is used in the first information,
wherein (a) the paging information is obtained without determining
whether or not the paging information is intended for the user
equipment, and (b) the paging information is obtained based on the
physical layer radio resources identified by the portion of the
first information.
2. The method of claim 1, wherein: the paging information comprises
another identifier indicating whether or not the paging information
is intended for the user equipment; and the first information
further indicates a coding scheme for the paging information.
3. The method of claim 2, wherein the identifier is used by
reserving and allocating a part of scheduling identifiers.
4. The method of claim 3, wherein the user equipment determines the
identifier used in the first information according to a
discontinuous reception (DRX) cycle and the user equipment is in
Radio Resource Control (RRC) connected state.
5. The method of claim 4, wherein the identifier indicates that the
paging information is transmitted through the shared channel in the
first TTI.
6. The method of claim 5, wherein: the physical layer radio
resources for the paging information is flexibly allocated
according to whether or not the paging information is transmitted
through the shared channel.
7. The method of claim 3, wherein: the physical layer radio
resources for the paging information is flexibly allocated
according to whether or not the paging information is transmitted
through the shared channel.
8. The method of claim 1, wherein: the identifier has a
predetermined value which indicates an existence of the paging
information in a corresponding TTI.
9. A communication apparatus for a user equipment, comprising: a
circuitry, wherein the circuitry is configured to: cause the user
equipment to receive at least a part of a frame, wherein (a) the
frame consists of a plurality of transmission time intervals (TTI)
including a first TTI, (b) the first TTI comprises a control
channel and a shared channel, (c) first information is received at
the user equipment through the control channel of the first TTI,
and (d) at least a portion of the first information identifies
physical layer radio resources; determine that a first indicator an
identifier is used in the first information; and cause the user
equipment to obtain paging information transmitted through the
shared channel in the first TTI in response to determining that the
identifier is used in the first information, wherein (a) the paging
information is obtained without determining whether or not the
paging information is intended for the user equipment, and (b) the
paging information is obtained based on the physical layer radio
resources identified by the portion of the first information.
10. The apparatus of claim 9, wherein: the paging information
comprises another identifier indicating whether or not the paging
information is intended for the user equipment; and the first
information further indicates a coding scheme for the paging
information.
11. The apparatus of claim 10, wherein the identifier is used by
reserving and allocating a part of scheduling identifiers.
12. The apparatus of claim 11, wherein the circuitry is configured
to determine the identifier used in the first information according
to a discontinuous reception (DRX) cycle and the user equipment is
in Radio Resource Control (RRC) connected state.
13. The apparatus of claim 12, wherein the identifier indicates
that the paging information is transmitted through the shared
channel in the first TTI.
14. The apparatus of claim 13, wherein: the physical layer radio
resources for the paging information is flexibly allocated
according to whether or not the paging information is transmitted
through the shared channel.
15. The apparatus of claim 11, wherein: the physical layer radio
resources for the paging information is flexibly allocated
according to whether or not the paging information is transmitted
through the shared channel.
16. The apparatus of claim 9, wherein: the identifier has a
predetermined value which indicates an existence of the paging
information in a corresponding TTI.
17. An apparatus for wireless communication, comprising: a
circuitry, wherein the circuitry is configured to: cause the
apparatus to receive at least a part of a frame, wherein (a) the
frame consists of a plurality of transmission time intervals (TTI)
including a first TTI, (b) the first TTI comprises a control
channel and a shared channel, (c) first information is received at
the apparatus through the control channel of the first TTI, and (d)
at least a portion of the first information identifies physical
layer radio resources; determine that an identifier is used in the
first information; and cause the apparatus to obtain paging
information transmitted through the shared channel in the first TTI
in response to determining that the identifier is used in the first
information, wherein (a) the paging information is obtained without
determining whether or not the paging information is intended for
the user equipment, and (b) the paging information is obtained
based on the physical layer radio resources identified by the
portion of the first information.
18. The apparatus of claim 17, wherein: the paging information
comprises another identifier indicating whether or not the paging
information is intended for the apparatus; and the first
information further indicates a coding scheme for the paging
information.
19. The apparatus of claim 18, wherein the identifier is used by
reserving and allocating a part of scheduling identifiers.
20. The apparatus of claim 19, wherein the circuitry is configured
to determine the identifier used in the first information according
to a discontinuous reception (DRX) cycle and the apparatus is in
Radio Resource Control (RRC) connected state.
21. The apparatus of claim 20, wherein the identifier indicates
that the paging information is transmitted through the shared
channel in the first TTI.
22. The apparatus of claim 21, wherein: the physical layer radio
resources for the paging information is flexibly allocated
according to whether or not the paging information is transmitted
through the shared channel.
23. The apparatus of claim 19, wherein: the physical layer radio
resources for the paging information is flexibly allocated
according to whether or not the paging information is transmitted
through the shared channel.
24. The apparatus of claim 17, wherein: the identifier has a
predetermined value which indicates an existence of the paging
information in a corresponding TTI.
Description
TECHNICAL FIELD
The present invention relates to a method for transmitting paging
information in a cellular system; and, more particularly, to a
method for transmitting paging information notifying generation of
downlink information from a base station to a terminal in a
cellular system for providing a packet service.
BACKGROUND ART
A conventional cellular system is operated by fixedly allocating a
transport channel and a physical channel for paging information. In
particular, in a 3.sup.rd Generation Partnership Project (3GPP)
system of a Wideband Code Division Multiple Access (WCDMA) method,
a paging channel (PCH) is a transport channel and is transmitted
through a secondary common control physical channel (S-CCPCH),
which is a physical layer channel for transmitting common control
information. A forward access channel (FACH), which is a transport
channel having a similar attribute to the paging channel, and a
paging channel can be mapped to the S-CCPCH.
In a conventional WCDMA system, a radio resource is assigned by
allocating a code index of orthogonal variable spreading factor
(OVSF) with orthogonality. Therefore, an individual OVSF code index
is allocated to the S-CCPCH and another physical layer channel may
not use or share the OVSF code index allocated to the S-CCPCH.
Although there is no information to be transmitted from a base
station to a terminal through the transport channel PCH and FACH at
a given time, the physical layer channel S-CCPCH exists. Although
there is no transmitted information in the S-CCPCH, the OVSF code
index and another radio resource, i.e., power, are allocated and
thus radio resources are wasted.
A general paging procedure is as follows. Terminals are included in
a specific paging group defined for an efficient paging procedure
in a system. Therefore, the base station notifies that a paging
message arrives at terminals included in a corresponding group
through the paging indication channel (PICH), which is a physical
layer channel. The terminals monitor the paging indication channel
every monitoring cycle. As a result of monitoring, when it is
sensed that indication information corresponding to the group
including the terminal exists in the paging indication channel, the
terminals search PCH information transmitted to the S-CCPCH channel
and decode paging information that an identifier (ID) such as
international mobile subscriber identity (IMSI), temporary mobile
subscriber identity (TMSI), UMTS terrestrial radio access
network-radio network temporary identifier (U-RNTI) exists. The
terminals decoding the paging information performs following
procedures corresponding to the paging information.
Also, a plurality of S-CCPCHs may be operated to obtain a paging
capability according to an environment of the base station and the
capacity for subscribers of the base station. When the base station
is installed based on a cell specific parameter, the S-CCPCH is
statically operated. The radio resource allocating method, which is
statically operated in consideration of the maximum capacity, has a
merit that a circuit based-system is statically operated, but has a
problem that the limited radio resource is wasted.
A long term evolution (LTE) system standardized in 3GPP to provide
diverse packet services is a packet based-system. An object of the
LTE system is to provide a pure packet service. Therefore, in the
LTE system for providing a packet service having a burst
characteristic, efficient and variable methods for utilizing radio
resources are needed. Accordingly, a research for simplifying and
integrating diverse kinds of transport channels operated in the
conventional WCDMA method are being progressed.
DISCLOSURE
Technical Problem
An embodiment of the present invention is directed to providing a
method for transmitting paging information which can improve
applicability of a limited radio resource by variably and flexibly
setting up and mapping a transport channel and a physical channel
in order to transmit information notifying start of downlink
information from a base station to a terminal in a cellular system
for packet transmission.
Other objects and advantages of the present invention can be
understood by the following description, and become apparent with
reference to the embodiments of the present invention. Also, it is
obvious to those skilled in the art of the present invention that
the objects and advantages of the present invention can be realized
by the means as claimed and combinations thereof.
Technical Solution
In accordance with an aspect of the present invention, there is
provided a method for transmitting paging information in a cellular
system, including the steps of: forming a paging channel (PCH) in a
transport channel corresponding to generation of paging
information; setting a paging indication channel (PICH) based on
the paging information and forming the paging indication channel in
a radio resource of a physical layer; and allocating the paging
channel to the radio resource of the physical layer.
In accordance with another aspect of the present invention, there
is provided a method for transmitting paging information in a
cellular system, including the steps of: creating a paging channel
including a paging message (P-MSG) correspondingly to generation of
paging information; allocating the paging message to a radio
resource of a physical channel; creating scheduling information
corresponding to the paging message; and allocating the scheduling
information to a physical layer control channel.
Advantageous Effects
The present invention can improve applicability of a limited radio
resource by variably and flexibly setting up and mapping a
transport channel and physical channel in a method for transmitting
information notifying start of downlink information from a base
station to a terminal in a cellular system for packet
transmission.
Also, the present invention can maximally apply a limited radio
resource by variably operating a procedure of notifying generation
of downlink information to initiate or restart downlink information
transmission from the base station to the terminal in a packet
based-cellular system.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flowchart describing a paging information transmitting
procedure in accordance with a first embodiment of the present
invention.
FIG. 2 shows a transport channel and a physical channel in
accordance with the first embodiment of the present invention.
FIG. 3 is a flowchart describing a paging information transmitting
procedure in accordance with a second embodiment of the present
invention.
FIG. 4 shows the transport channel and the physical channel in
accordance with the second embodiment of the present invention.
FIG. 5 shows a group identifier (ID) to which a part of a terminal
scheduling ID is allocated in accordance with an embodiment of the
present invention.
FIG. 6 shows a physical layer control channel to which scheduling
ID information is allocated and a radio resource to which paging
information is variably allocated in accordance with the second
embodiment of the present invention.
FIG. 7 shows an example that the radio resource of the physical
layer is variably allocated and operated corresponding to
generation of the paging information in accordance with an
embodiment of the present invention.
BEST MODE FOR THE INVENTION
The advantages, features and aspects of the invention will become
apparent from the following description of the embodiments with
reference to the accompanying drawings, which is set forth
hereinafter. Therefore, those skilled in the field of this art of
the present invention can embody the technological concept and
scope of the invention easily. In addition, if it is considered
that detailed description on a related art may obscure the points
of the present invention, the detailed description will not be
provided herein. A technology outline of a cellular system for
providing a packet service to which the present invention is
applied is will be described in brief, and the preferred
embodiments of the present invention will be described in detail
hereinafter with reference to the attached drawings.
The cellular system for the packet service may maximize
applicability of a limited radio resource by sharing the radio
resource between a base station and a terminal in consideration of
a bust characteristic of packet service data differently from a
circuit. A 3.sup.rd Generation Partnership Project (3GPP) long term
evolution (LTE) system, which is being standardized as the cellular
system for the packet service should support bandwidth scalability
of a bandwidth ranging 1.25 MHz to 20 MHz. In designing of a
general system, scalability for 5 MHz, 10 MHz, and 20 MHz
bandwidths is assumed.
Conventional paging information is transmitted to the terminals in
an idle state, i.e., the terminals performing low power
consumption, through a paging channel, and the terminals providing
a service through a dedicated channel. In the LTE system, the
terminals are defined as following states in consideration of Radio
Resource Control (RRC) and Medium Access Control (MAC).
In consideration of RRC, the terminal state is managed as
RRC_Connected and RRC_Idle states. The RRC_Connected denotes a
state that the RRC is connected between the base station and the
terminal. In the RRC_Connected state, the base station manages
mobility of the terminal, and stores and manages a RRC context. The
RRC_Idle denotes a state that the RRC is not connected between the
base station and the terminal. In the RRC_Idle state, access
GateWay (aGW) manages mobility of the terminal. The terminal in the
RRC_Idle state performs a low power consumption, i.e., power saving
operation, according to a discontinuous reception (DRX) cycle based
on RRC configuration.
In the RRC_Connected state, an MAC mode is divided into a
MAC_Active mode and an MAC_Dormant mode and is controlled for a low
power consumption of the terminal according to activity factors
occupying the radio resource between the terminal and the base
station. The MAC_Active mode means that uplink synchronization of
the physical layer is maintained and packet information is
transmitted/received between the base station and the terminal. The
MAC_Dormant mode means that a buffer is empty without
transmitting/receiving packet information between the base station
and the terminal in the MAC_Active. When a packet is not
transmitted/received for a predefined time in the MAC_Active mode,
the terminal transfers to the MAC_Dormant mode. In the MAC_Dormant
mode, a low power consumption operation is performed according to
discontinuous reception (DRX)/discontinuous transmission (DTX)
cycle by a scheduler. Also, it may not to maintain the uplink
synchronization of the physical layer by control of the base
station.
When it is considered that paging notifying generation of
information to be transmitted on the downlink should be performed
on the terminals performing the low power consumption according to
the DRX/DTX cycle, paging of the LTE system is applied to the
terminals in the RRC_Idle state and the MAC_Dormant mode. In the
present invention, paging is performed on the terminals in the
RRC_Idle state, and a method using a paging indication channel,
which is a physical layer channel, and a method to be applied
without the paging indication channel, are provided.
In the packet transmission system, since the terminals in the base
station share radio resources, scheduling information for
addressing the radio resource allocated to a terminal or a terminal
group should be transmitted such that the terminals in the base
station can recognize the scheduling information. Accordingly, the
present invention provides a method for transmitting scheduling
information through a physical layer control channel.
FIG. 1 is a flowchart describing a paging information transmitting
procedure in accordance with a first embodiment of the present
invention and FIG. 2 shows a transport channel and a physical
channel in accordance with the first embodiment of the present
invention.
In the present embodiment, paging information is transmitted to the
terminals in the RRC_Idle state through the paging indication
channel, which is a physical channel. A paging information
transmitting procedure will be described in detail according to the
embodiment with reference to FIGS. 1 and 2.
When paging information 1 on a terminal or a group of terminals at
a predetermined time is generated at step S110, the base station
has a paging channel (PCH) included in the transport channel based
on the generated paging information at step S120.
The scheduler performs scheduling on broadcasting channel (BCH)
information, created paging channel information and, traffic
information to be transmitted to the terminal based on a
transmission time interval (TTI) at step S130.
In consideration of a DRX cycle for a low power consumption of the
terminals in the RRC_Idle state, the base station sets up a paging
indication channel 6 corresponding to the terminal or the terminal
group indicated by the paging information and forms the paging
indication channel 6 at step S140 such that the terminal in the
system can be divided into groups.
The base station performs mapping on the paging channel with a
radio resource block location 9 of a physical layer allocated at
TTI 8 as a fixed size and location, e.g., a time index and a
sub-carrier index, based on a T.sub.paging indication channel-PCH
value 7 at step S150, modulates and codes a radio resource based on
the pre-set up modulating and coding methods, and transmits the
radio resource to the terminal at step S160. The T.sub.paging
indication channel-PCH value is a parameter notifying a time
difference between the paging indication channel and the TTI that
the paging channel is transmitted. The T.sub.paging indication
channel-PCH value is set up as a multiple TTI.
In the present embodiment, a method for dividing a location of the
physical layer radio resource block for paging channel transmission
into paging indication channel groups, and fixing and allocating
the location of the physical layer radio resource block according
to each group is adopted. When no paging information is generated
(see 2 of FIG. 2), the paging channel does not exist in the
transport channel of the radio frame (see 5 of FIG. 2). In this
case, the paging indication channel is not also set up. Therefore,
downlink shared channel (DL-SCH) information for user data
transmission and not paging information of the paging channel is
transmitted to the radio resource block location of the physical
layer fixed and allocated for the paging channel.
FIG. 3 is a flowchart describing a paging information transmitting
procedure in accordance with a second embodiment of the present
invention and FIG. 4 shows the transport channel and the physical
channel in accordance with the second embodiment of the present
invention. A paging information transmitting procedure will be
described in detail with reference to FIGS. 3 and 4.
When paging information 1 for a terminal or a terminal group is
generated at a given time at step S310, the base station creates a
paging channel 10 including a paging message (P-MSG) based on the
generated paging information at step S320.
A scheduler performs scheduling on broadcasting channel (BCH)
information formed based on a radio frame unit, paging message
information and traffic information to be transmitted to the
terminals on the basis of TTI at step S330.
The paging message is variably allocated to a radio resource 12 of
the physical channel at step S340.
Scheduling information is created at step S350, allocated to the
physical layer control channel at step S360, and modulated and
coded according to the pre-determined modulating and coding
methods, and transmitted to the terminal at step S370.
The scheduling information is the minimum information for
addressing the allocated radio resource and includes a terminal
scheduling identifier (ID), radio resource allocation information
indicating a location of the allocated radio resource block,
modulation method information and coding method information. The
scheduling information may further include additional information
for operation such as retransmission and multiple antenna
application.
The terminal scheduling ID is an ID for identifying a specific
terminal or a terminal group between the terminal and the scheduler
of the base station. As shown in FIG. 5, the present invention is
operated by reserving and allocating a part of the information
included in the terminal scheduling ID as a group ID for paging
information. The group ID is an ID used by reserving and allocating
a part of a scheduling ID (i.e., a cell radio network temporary
identifier (C-RNTI)) for uniquely identifying a terminal. A base
station may operate by reserving at least one scheduling ID.
Meanwhile, the group ID may be used to indicate downlink
information transmission below.
The radio resource allocation contents inform a radio resource
location or section of an Orthogonal Frequency Division
Multiplexing (OFDM) method, which is divided into a frequency
region and a time region. The modulation method contents inform
which modulation method among a plurality of modulation methods
applied in the LTE system is applied. The coding method contents
inform which coding method among a plurality of coding methods
applied in the LTE system is applied.
According to the second embodiment of the present invention, a
paging procedure may be performed on the terminals in the RRC_Idle
state without the physical paging indication channel (PICH). In the
present embodiment, when paging information is not generated, radio
resource applicability (utilizable level) can be maximized by
transmitting only scheduling information for the terminals without
scheduling information for a paging message in the physical layer
control channel information, and mapping and using available
physical layer radio resources as DL-SCH for data information
transmission. Also, the radio resource applicability may be
optimized through a method for flexibly allocating the radio
resource of the physical layer based on the quantity of the
generated paging information.
Part of the terminal scheduling ID may be reserved, allocated and
used by a group ID, and more than one group ID may be reserved and
allocated according to the capability of the terminal. The group ID
may be broadcasted through a system broadcasting channel. When the
terminal is in a network, the group ID is managed according to each
group and managed through modification/update based on a network
environment.
FIG. 6 shows a physical layer control channel to which scheduling
ID information is allocated and a radio resource to which paging
information is variably allocated in accordance with the second
embodiment of the present invention.
According to a procedure in accordance with the embodiment
described above, a radio resource as shown in FIG. 6 is formed and
transmitted to the terminal. The terminal receiving the radio
resource searches a control channel 11 of the physical layer,
recognizes the group ID reserved and allocated for transmission of
paging information, which is given for the scheduler of the base
station to identify the terminal or the terminal group in a cell,
receives and decodes paging information transmitted to the radio
resource block 12 based on radio resource block addressing
information. That is, the terminals may recognize whether the
paging message on the terminal group exists by searching a control
channel and checking existence of the group ID reserved and
allocated for transmission of the paging information in the
scheduling information of the control channel transmitted from the
base station. Therefore, when there is no group ID for the paging
message indicating own group in the control channel, the terminals
determine that the paging message does not exist, and continuously
performs a discontinuous reception operation. When the group ID
exists, the terminals stop the discontinuous reception operation
and receive the paging message that the base station transmits on
the radio resource addressed by the group ID.
In this case, a modulating and coding method of the block
transmitting the paging message broadcasts the paging message to
the entire cell based on the system information, or may transmit
the paging message through the scheduling information of the
physical layer control channel as described above.
In the RRC_Connected state, when a state for low power consumption
is controlled according to an activity factor occupying the radio
resource between the terminal and the base station in an MAC point
of view, the terminal is operated by being divided into a duration
of monitoring downlink data and a duration of sleeping for
performing low power consumption according to the discontinuous
reception/discontinuous transmission (DRX/TDX) cycle.
In the RRC_Connected state, when the terminal performs power saving
operation of monitoring a downlink signal on monitoring duration
according to the discontinuous reception/discontinuous transmission
cycle, a paging procedure similar to the RRC_Idle state is required
in the monitoring duration of the terminal to start transmitting
information on the downlink. The paging procedure is defined as
indication to be differentiated from paging in the RRC_Idle state.
Indication information is information notifying start of
transmitting downlink information from the base station to the
terminal like the paging information. Herein, in the RRC_Idle
state, the RRC layer of the base station is in charge of control,
but in the RRC_Connected state, the RRC layer or the MAC layer is
in charge of control relatively to the function of the
scheduler.
When indication information for downlink information transmission
in the RRC_Connected state is transmitted, the paging information
transmitting method according to the embodiment described above may
be used without any change. That is, the paging information
transmitting method is adaptable by substituting indication
information for downlink information transmission for the paging
information in the embodiment described above.
To be specific, the scheduler of the base station transmits
scheduling information, which is transmitted to the physical layer
control channel according to the configured discontinuous
reception/discontinuous transmission cycle, including the terminal
scheduling ID and radio resource allocation information for the
terminal which should receive indication information notifying
downlink information transmission, or the terminal group.
Therefore, in the duration that the terminal in the RRC_Connected
state performs monitoring according to the configured discontinuous
reception/discontinuous transmission cycle, the terminal performing
low power consumption operation according to the activity factor of
the terminal searches the control channel of the physical layer
transmitted from the base station, recognizes a scheduling ID for
the terminal or the group ID reserved and allocated for indication
allowed to identify a terminal or a group in the cell by the
scheduler of the base station, and receives and decodes the
indication message transmitted on the radio resource block using
the radio resource allocation information. In this case, it is
possible to broadcast the modulating and coding method of the block
transmitting the indication to the entire cell through the system
information, or to transmit the modulating and coding method
through the scheduling information of the physical layer control
channel.
It is also possible to include only the group ID reserved and
allocated for the indication of downlink information in the
physical layer control channel in order to reduce overhead due to
control information transmission by reducing the size of the
physical layer control channel information. In this case, the radio
resource block 12 of the physical channel for the indication
information can be fixed and operated in the inside of the
corresponding TTI.
When the method of the second embodiment transmitting the
indication message through the control channel and the DL-SCH of
the physical layer to notify downlink information transmission for
the terminals in the RRC_Connected state is applied, the DL-SCH and
the physical layer control channel can be used in the same method
although the activity attribute of the terminal is different in the
RRC_Connected state under control of the scheduler and the MAC.
FIG. 7 shows an example that the radio resource of the physical
layer is variably allocated and operated corresponding to
generation of the paging information in accordance with an
embodiment of the present invention.
As shown in FIG. 7, only when paging information for the terminals
in the RRC_Idle state or downlink indication information for the
terminals in the RRC_Connected state is generated, the present
invention occupies the radio resource of the physical layer and may
efficiently operate the limited radio resource.
As described above, the technology of the present invention can be
realized as a program and stored in a computer-readable recording
medium, such as CD-ROM, RAM, ROM, floppy disk, hard disk and
magneto-optical disk. Since the process can be easily implemented
by those skilled in the art of the present invention, further
description will not be provided herein.
While the present invention has been described with respect to
certain preferred embodiments, it will be apparent to those skilled
in the art that various changes and modifications may be made
without departing from the scope of the invention as defined in the
following claims.
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